1. Field of Invention
The present invention relates to an input device, more particularly to an electronic input device with piezoelectric sensor.
2. Description of Related Art
A conventional art of galvanic skin response (GSR) is often adopted in a physiology measuring device used to measure the electrical resistance of the skin generated due to vasoconstriction, vasodilatation or secretion of the sweat gland when a person has emotional arousal. When the measuring device is in contact with human's skin, physiological pressure and emotion can therefore be quantified by analyzing the changes of the electrical resistance of the human's skin.
Skilled people in the art have adopted the above mentioned measuring device on surfaces of an electronic input device, e.g. a mouse, a keyword or a telephone. So when a user touches electrodes provided on the surfaces of the input devices, the current physiology status of the user is measured and proper relative information is also obtained. Thus a purpose of monitoring the user's physiology status is achieved (e.g. sending a signal indicating that the user needs a rest), or a purpose of indicating the user to operate the electronic input device is achieved (e.g. after sensing a command is finished then another command is proceed).
However, since not every user uses an input device with same operating habit, when they are using the input device, the pressing levels on the galvanic skin electrodes are varied. That is, when the areas of the electrodes on which a user's skin touches and the applied pressure are changed, the measured galvanic skin resistance is therefore changed. Hence, both the contact areas of the electrodes and the pressure applied on the electrodes need to be put into considerations for obtaining a more effective and accurate data, otherwise the operations of monitoring or indicating according to the invalid data are worthless.